WHAT IS A PLACEBO?
Placebos have been defined as follows:
Inert substances which cause symptom relief (e.g. ‘My headache went away after
having a sugar pill’).
Substances that cause changes in a symptom not directly attributable to specific or
real pharmacological action of a drug or operation (e.g. ‘After I had my hip operation
I stopped getting headaches’).
Any therapy that is deliberately used for its non-specific psychological or physio-
logical effects (e.g. ‘I had a bath and my headache went away’).These definitions illustrate some of the problems with understanding placebos. For
example:
What are specific/real versus non-specific/unreal effects? For example, ‘My head-
aches went after the operation, is this an unreal effect (it wasn’t predicted) or a real
effect (it definitely happened)?’
Why are psychological effects non-specific? (e.g. ‘I feel more relaxed after my
operation – is this a non-specific effect?’).
Are there placebo effects in psychological treatments? For example, ‘I specifically
went for cognitive restructuring therapy and ended up simply feeling less tired. Is this
a placebo effect or a real effect?’The problems inherent in the distinctions between specific versus non-specific effects
and physiological versus psychological effects are illustrated by examining the history of
apparently medically inert treatments.A HISTORY OF INERT TREATMENTS
For centuries, individuals (including doctors and psychologists) from many different
cultural backgrounds have used (and still use) apparently inert treatments for various
different conditions. For example, medicines such as wild animal faeces and the blood
of a gladiator were supposed to increase strength, and part of a dolphin’s penis was
supposed to increase virility. These so-called ‘medicines’ have been used at different
times in different cultures but have no apparent medical (active) properties. In addition,
treatments such as bleeding by leeches to decrease fever or travelling to religious sites
such as Lourdes in order to alleviate symptoms have also continued across the years
without any obvious understanding of the processes involved. Faith healers are another
example of inert treatments ranging from Jesus Christ, Buddha and Krishna. The
tradition of faith healers has persisted, although our understanding of the processes
involved is very poor.
Such apparently inert interventions, and the traditions involved with these practices,
have lasted over many centuries. In addition, the people involved in these practices
have become famous and have gained a degree of credibility. Furthermore, many of thePLACEBOS AND THE INTERRELATIONSHIP BETWEEN BELIEFS, BEHAVIOUR AND HEALTH 309